1. Field of the Invention
The present invention relates to a battery information acquiring apparatus that acquires battery information of a battery cell in a battery pack made up of a plurality of battery cells connected in series or in parallel, and transmits the battery information to a management unit that manages the battery pack.
2. Related Art
As supply of battery power for electric cars or industrial vehicles, battery packs in which many battery cells of low voltage and low capacity are connected in series or in parallel are used to obtain a high voltage and high capacity voltage. Safe operation of a battery pack requires a battery information management system that monitors a voltage and temperature or the like of each battery cell.
For example, JP-A 2005-135762 (Kokai) proposes a state monitoring apparatus using radio waves as a scheme for realizing a battery information management system. This configuration supplies a power supply voltage for the state monitoring apparatus from a battery cell or radio tag and involves a problem that when a power supply voltage is supplied from the battery cell, power is also consumed during standby during which control signals and battery information are not communicated. Furthermore, since the radio tag has poor power conversion efficiency, power consumption on the supply side of power increases due to supply of power to all state monitoring apparatuses.